Preheat your oven to 400°F (200°C).
In a skillet, brown the ground meat over medium heat.
Add the chopped onion and diced carrots; cook until softened.
Stir in the tomato paste and mix well.
Pour in the beef broth and Worcestershire sauce; let it simmer for 5 minutes.
Add frozen peas; season with salt and pepper.
Transfer the meat mixture to a baking dish.
Spread the mashed potatoes evenly over the meat mixture.
Sprinkle cheese on top if desired.
Bake in the preheated oven for 25-30 minutes or until golden brown.